replace checking for ->read/->aio_read presence with check in ->f_mode
Since we are about to introduce new methods (read_iter/write_iter), the
tests in a bunch of places would have to grow inconveniently. Check
once (at open() time) and store results in ->f_mode as FMODE_CAN_READ
and FMODE_CAN_WRITE resp. It might end up being a temporary measure -
once everything switches from ->aio_{read,write} to ->{read,write}_iter
it might make sense to return to open-coded checks. We'll see...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 8153396..75eb713 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -128,6 +128,10 @@
#define FMODE_ATOMIC_POS ((__force fmode_t)0x8000)
/* Write access to underlying fs */
#define FMODE_WRITER ((__force fmode_t)0x10000)
+/* Has read method(s) */
+#define FMODE_CAN_READ ((__force fmode_t)0x20000)
+/* Has write method(s) */
+#define FMODE_CAN_WRITE ((__force fmode_t)0x40000)
/* File was opened by fanotify and shouldn't generate fanotify events */
#define FMODE_NONOTIFY ((__force fmode_t)0x1000000)